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Blinking LED circuit



On Fri, Sep 24, 2004 at 08:36:18AM -0400, Doug Sweetser wrote:
> Hello:
> I need a pair of red blinking LEDs for a video project, one where the
> first blinks, there is a 0.5 sec gap, the second one goes, then a 3.5
> second gap, and then that cycle repeats.
> 

So you want two lights that blink at four second intervals, with
the second one starting 0.5 sec after the first, right?

There are nearly an infinite number of ways to build it, but its
easiest to buy it pre-made.

Its very easy to build. go to Rat shack and talk to the old guy behind
the counter (The young may also be helpful, but the old guy is the best
bet).  If they don't have some pre-made stuff that you can hook together
look for the books by Forest M Mims., 

Especially his "Engineers Mini-Notebooks", about 2 bucks each.  If you
see the one one r555 timer circuits, snag it.  Also recommend  "digital
logic circuits" and "basic semiconductor circuits" in the same series
(for a total of $5 :-) )


Your biggest problems are:  

	power supply  (easy if batteries are OK)
	form factor   What does it have to fit in
	accuracy      what level of error can you live with?
	              (plus or minus how much)

> 
-- 
Linux/Open Source.  Now all your base belongs to you, for free.
============================================================
Idealism:  "Realism applied over a longer time period"

Jeff Kinz, Emergent Research, Hudson, MA.




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